Review of Warrnambool Flood Controls - Things You Might Like to Know
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Why were the flood studies undertaken?
Flooding can have an enormous impact on individuals, families, communities and
businesses. One of the best ways to mitigate against the effects of flooding is through
appropriate building design and land use planning. Modern flood studies help us to
make better planning decisions.
The existing flood controls in the Warrnambool Planning Scheme were prepared in the
late 1980s and early 1990s and do not match the current flood data available and used
by the Glenelg Hopkins Catchment Management Authority.
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What are the benefits of the studies?
The studies will improve land use planning and development decisions to minimise the
risks to the community from flooding. The studies assist emergency service authorities
in preparing for and responding to a flood emergency in Warrnambool.

What is the difference between ‘Flooding’ and ‘Inundation’?
Flooding: relates to areas that have free flowing floodwater, and usually comprises the
high-hazard portion of a floodplain. These areas are usually the areas of deeper flow or
the areas where higher velocities occur, and where development is to be avoided.
Inundation: relates to areas on the fringe of floodplains that can be expected to get wet
in times of heavy rainfall or storm surge, but not retain floodwater.

What is a ‘1-in-100’ year flood?
A ‘1-in-100’ year flood is a level of flooding that has a 1% chance of occurring in any
year. It is considered a very large, rare flood event and is used to apply minimum design
standards for new development in Victoria.

Why is Council making changes to the flood mapping?
The flood studies have produced new and revised flood mapping for the Merri River and
Russells Creek catchments.
The new and revised flood mapping has resulted in:
 Changes to the existing flood mapping in North Warrnambool and South
Warrnambool.
 Entirely new mapping for some parts of the Russells Creek catchment and some
areas of Dennington.
Changes to the Warrnambool Planning Scheme are being proposed in order to ensure
the most up to date mapping is available to the public and is used by Warrnambool City
Council when making decisions on land use and development. This will also ensure
consistent flood mapping is used by both the Glenelg Hopkins Catchment Management
Authority and Council.

What is the Urban Floodway Zone? How has the Urban Floodway Zone been
applied?
The Urban Floodway Zone (UFZ) is a planning control that applies to areas that have the
greatest risk and frequency of being affected by flooding. It is proposed to apply the UFZ
to urban areas that are undeveloped.
A planning permit will be required for all buildings and works within the UFZ. However,
use of the land for a dwelling within the UFZ part of your land will be prohibited.
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
What is the Floodway Overlay? How has the Floodway Overlay been applied?
The Floodway Overlay (FO) is a planning control that applies to areas that have a high
risk and frequency of being affected by flooding. It is proposed to apply the FO to urban
areas that have been developed for residential purposes, and to rural areas.
A planning permit will be required for all buildings and works within the Floodway
Overlay.
What is the Land Subject to Inundation Overlay? How has the Land Subject to
Inundation Overlay been applied?
The Land Subject to Inundation Overlay (LSIO) is a planning control that applies to areas
where flooding is considered less severe. It is proposed to apply the LSIO to flood fringe
areas to ensure new buildings are designed in such a way that free flow of floodwaters
can occur, and flood damage is minimised.
A planning permit will be required for all buildings and works within the Land Subject to
Inundation Overlay.

Why is the Land Subject to Inundation Overlay being removed from my property?
The revised flood mapping shows that your property has a lower flooding risk than
previously thought therefore, the overlay is being removed from that part of your property
which is no longer affected by flooding.

What impact will the works currently being undertaken in Russells Creek have on
my property?
The North Warrnambool Flood Mitigation Project may also reduce or remove the flood
controls from your property. Council is aware that some landowners may question why
the controls are being applied now, and why Council doesn’t simply wait until completion
of the works within the creek. Because the flood studies have been prepared on a
catchment-wide basis, it is important that they are implemented at the same time. At
completion of the works along the creek, any properties that no longer require flood
protection will have the flood controls either reduced or removed from their properties.

Will the changes affect my insurance?
Insurance premiums for flooding are generally affected by the extent of the most recent
flood studies, regardless of whether the flood studies are in the planning scheme. As
such, Amendment C78 should not affect insurance premiums as they should already be
based on this most recent data. Please contact your insurance provider to discuss any
details of your own personal circumstances and insurance policy.

Will the changes affect my rates?
Planning controls govern future use and development of land. They do not directly
influence rates applied to land. The proposed changes to the planning controls will
therefore not mean a direct change to rates.
Council rates are, in part, based on property valuations. Property valuations are affected
by numerous factors. Location, size, amenity, building use, rental return, and quality of
buildings, etc., all play a role in determining the value of a property. If the valuation
changes for a property, then the rates may also change.